SE544151C2

SE544151C2 - Shock-absorbing material for a head worn device

Info

Publication number: SE544151C2
Application number: SE2050196A
Authority: SE
Inventors: Holst Hans Von
Original assignee: Cenesy Ab
Priority date: 2020-02-21
Filing date: 2020-02-21
Publication date: 2022-01-11
Also published as: SE2050196A1

Abstract

There is provided a head-worn device (100) such as a helmet, a hat or a head band for protecting the head against impact shock, the head worn device (100) comprising an elastomeric sheet (2) that has a plurality of deformable support members (7) configured to be in contact with the head or a second layer of the head-worn device (100), said support members (7) being configured to be deformed upon shock, where the support members (7) has apertures (11) from one side of the elastomeric sheet to the other side of the elastomeric sheet (2), where the hardness of the elastomeric sheet (2) is from 40 Shore A to 80 Shore A.

Description

Shock-absorbing materialj Field of the invention This invention relates to a shock-absorbing material that can be used for example in a hel- met or in a horseshoe.

Background Serious head injuries, such as traumatic brain injuries, occur in traffic, in the workplace andduring sports activities. There is still an unacceptable number of head injuries worldwide.There is a need for an improved helmet, in particular a helmet that absorbs oblique impacts,that is impacts that are not perpendicular to the surface of the helmet. Thus, it would be advantageous to prevent traumatic brain injuries by an improved head worn device.

The legs of horses are subject to high stress when the horse is walking, trotting or galloping.

This frequently leads to fractures or other injuries.

Summarv of the invention helmet, a hat or a head band for protecting the head against impact shock, the head worn-_» There may be two parallel sheets of elastomeric material and where the support membersare facing towards each other. The two parallel sheets are essentially immobile in relation to each other. The two parallel sheets may be glued together.

The height of the support members in relation to the total thickness of the elastomericsheet may be 25% -75 % ofthe total thickness ofthe elastomer layer (the thickness including the support members).

Drawings Fig. 1 is a schematic cross section of a helmet.

Fig. 2 is a schematic cross section of an elastomeric sheet.

Fig. 3 shows an elastomeric sheet.

Fig. 4 is a cross section of an elastomeric sheet along lines a-a of Fig. 3.

Fig. 5 is a cross section of an elastomeric sheet along lines b-b of Fig. 3.

Fig. 6 and 7 are cross sections of an elastomeric sheet that shows how it behaves duringimpact in a test setup.

Figs 8-11 are schematic cross sections of a part of a head worn device.

Fig. 12 is a schematic drawing of a hoof of a horse with a horseshoe.

Figs 13-14 are schematic drawings of a horseshoe.

Detailed description The head worn device may be a helmet, a hat or a head band.

The head worn device can be worn by a user to protect the user during sports activities(biking, skiing, riding, for example), in the workplace (such as at construction sites) or intraffic (such as by motorcyclists), or otherwise. When the head worn device is a hat or aheadband it may particularly useful in everyday use by the elderly, or by persons with poor balance.

The head worn device will now be described in more detail mainly in reference to a helmet.Fig 1. shows a head worn device 100 which is a helmet. The helmet comprises outer layer101, shock absorbing layer 102 and optional inner layer 103. lt should be observed that, forclarity, the thickness of the layers ~;'§~.'~"\<-.\-§§;¿\exaggerated in Fig. 1. The outer layer 101 and the inner layer are referred to herein as ”second layer".

The outer layer 101 is preferably in the form of a hard shell. The outer layer 101 may beformed in a polymer material such as for example polycarbonate, polyvinylchloride or ABSand may be reinforced with fibers such as carbon fibers or Kevlar. The outer layer 101 ispreferably thinner than the shock-absorbing layer 102. The outer layer 101 may serve thepurpose of distributing the shock of an impact to shock absorbing layer102. The outer layer 101 may also provide protection against perforation, such as cuts.

The optional inner layer 103 is suitable for resting against the head of a user and is prefer-ably comfortable for the user. The inner layer 103 may comprise cloth or mesh and mayhave padding. The inner layer 103 may be adjustable in order to provide a snug fit on thehead of the user. Hence inner layer 103 may be loosely fitted to shock absorbing layer 102in order to be adjustable to the head ofthe user. Inner layer 103 may comprise an adjusta-ble band that is circumferential in relation to the head of the user, in order to adjust the helmet to the head of the user.

The helmet may preferably an attachment device for attaching the helmet to the head. The attachment device is preferably a chin strap.

The outer layer 101, the inner layer 103 and the shock absorbing 102 layer are preferablyattached to each other. One or more layers may for example be glued together, in particularouter layer 101 and shock absorbing layer 102. The outer layer 101 is preferably thinnerthan the shock-absorbing layer 102 and may have a thickness of approximately 2-3 mm. Theinner layer 103 is also preferably thinner than the shock-absorbing layer 102 and may have a thickness of 2-3 mm. lt should be noted that each layer of the helmet may comprise additional layers providingdifferent functions as strength, shock, water proofing, insulation, colour, attachment be- tween layers (such as glue) or adjustability of helmet.

With reference to Fig. 2, the shock absorbing layer 102 comprises at least one layer of anelastomeric sheet 2 with a first side 6 and a second side 13 where the first side 6 has aplurality of deformable support members 7. The support members 7 are configured to bedeformed when the elastomeric sheet 2 receives an impact (see below with reference toFigs. 6 and 7). The main purpose of elastomeric sheet 2 is to provide shock absorption, thatis, to absorb the energy of an impact. This is achieved by the selection of the material ofelastomeric sheet 2 and the deformable supports members 7. The height of the supportmembers 7 in relation to the total thickness of the elastomeric sheet 2 may be 25% -75%, more preferably 30-60 % of the total thickness of the elastomer layer 2.

The thickness ofthe elastomeric sheet 2 is preferably from 5 to 20 mm, more preferably 8-15 mm, even more preferably 8-12 mm. The shock absorbing layer 102 preferably comprisesone or two of the elastomeric sheets 2 as described below. The thickness of the shock ab-sorbing layer 102 is preferably from 5-40, more preferably from 8-30 mm and even more preferably from 16-24 mm.

With reference to Figs. 3-5, the support members 7 may for example have the shape ofmembers separated by grooves 8 in a criss-cross pattern as seen in Figs. 3-5. The grooves 8may have a depth which is 25 % to 75 %, more preferably 30% -60% of the total thicknessof the elastomeric sheet 2. The grooves 8 may for example have a depth of for example 4-6 mm. The grooves 8 may have a width of 3-8 mm, preferably 4-6 mm. The walls 9 of thegrooves may be slanted as shown in Figs. 3-5, such that the profile ofthe grooves 8 is coni-cal. The grooves 8 may have a flat or a pointed top 10 (where a pointed top is shown in Figs. 3-5).

Figs. 2-5 shows one preferred embodiment of the support members 7 where the supportmembers have a square configuration (grooves meet at 90° angles), however the support members can have any suitable shape such as oval, circular etc.

The elastomeric sheet 2 is preferably provided with trough holes or apertures, hereafterreferred to as apertures 11. The apertures 11 go from the first side 6 of the elastomeric sheet 2 to the second side 13 of the elastomeric sheet 2. Apertures 11 are preferably perpendicular to the elastomeric sheet 2. The apertures 11 may have a diameter of from 4-7 mm and may be spaced for example 10-20 mm (c/c), preferably 13-18 mm apart. Theshortest distance between the holes may be 6-10 mm. The apertures 11 may be placed in the centre of the support members 7, as shown in Figs. 3-5.

The hardness of the elastomeric sheet 2 is preferably from 40 Shore A to 80 Shore A. Theelastomeric sheet 2 may be made from rubber or other suitable elastomer. The elastomermay be a polymer. Suitable elastomers for the elastomeric sheet 2 include various rubbermaterials for example: styrene butyric rubber, butyric rubber, isoprene rubber, butylic rub-ber, eten propen rubber, nitrilic butadiene rubber, chloroprene rubber, polyurethane rub- ber, acryl eten rubber and propene oxide rubber.

Figs. 6-7 show how the elastomeric sheet 2 behaves upon receiving an oblique shock (Fig.6) or a translational shock (Fig. 7) in a test set-up. The sheet 2 is covered by a shock-distrib-uting layer 5 which may mimic the behaviour of outer layer 101 of helmet 100 that it dis-tributes the shock to the elastomeric sheet 2. The elastomeric sheet 2 is placed on a hardsurface 4 and a weight is allowed to fall onto the surface 5 of the sheet 2. The arrows indi-cate the direction of impact on the shock-distributing layer 5 ofthe sheet 2. Figs. 6-7 shows an example of how support members 7 with apertures 11 behave on impact.

Figs. 8 to 11 show cross sections of a head worn device 100. Figs 8 and 9 show embodimentswith one elastomeric sheet 2, where the support members 7 ofthe elastomeric sheet points towards the inner layer 103 and the outer layer 101, respectively. ln Fig. 10, which is a preferred embodiment, two elastomeric sheets 2a, 2b are arrangedwith the supporting members 7 pointing towards each other thereby forming a shock-ab-sorbing layer 102 between outer layer 101 and inner layer 103. ln Fig. 11 the support mem-bers 7 are pointing in opposite directions, as one set of support members 7 point towardsthe inner layer 103 and one set of support members 7 point out towards the outer layer101. With reference to Figs. 10-11 it should be noted that the support members 7 of elas- tomeric sheets 2a, 2b may also point in the same direction. When two or more elastomeric layers 2a, 2b are used they may be attached to each first or second surfaces 6,13, for exam-ple with glue. Hence the plurality of elastomeric layers 2a, 2b may form a sandwich material.The plurality of elastomeric layers 2a, 2b may be essentially immobile in relation to each other.

When the helmet does not have inner layer 103 the shock absorbing layer 102 will be in bein contact with the head of the user. Hence in certain embodiments the support members 7 may be in contact with the head ofthe user.

The head worn device 100 may also be a hat or a head band. The hat or the head bandcomprises at least one elastomeric sheet 2. There may be one or more sheets 2, and thecombined thickness of the sheets 2 is preferably from 5 to 12 mm, i.e. somewhat slimmerthan in the case of a helmet. The elastomeric layer 2 may have a thickness of from 4 to 12mm in the case of a hat or a head band. ln addition, the hat or headband may comprise atleast one additional layer which may be made from for example cloth, such as wool, fleece,cotton or a synthetic polymer cloth, or other suitable material. The additional layer may bean outer soft layer or an inner layer. The additional layer may provide heat insulation, colour or provide a comfortable feeling to the head.

The head band may comprise a strip of elastomeric sheet 2. The strip may have a width offrom 5 to 10 cm. The head band is configured to be worn wear around the circumferenceof the head. The strip if elastomeric layer does not necessarily have to go around the fullcircumference of the head. ln particular the head band may be sized and located so that it protects the posterior part ofthe head thus preventing injury in a backwards fall.

The hat and the head band may be provided in different sizes. The size of the hat and thehead band may be adjustable, with the use of a size adjustment device. The adjustment device adjusts the circumference ofthe hat or the head band. ln a separate embodiment, shown in Figs. 12-14 the elastomeric sheet 2 is used in a horse- shoe 200 for a hoof 201 of a horse. The purpose of the horseshoe 200 is to reduce the impact shock in the leg of a horse when the horse is walking, trotting or galloping. Hence, itis provided a horseshoe 200 comprising the above elastomeric sheet 2. The thickness oftheelastomeric sheet 2 is preferable from 10 to 15 mm. The horseshoe is designed either as aclassic horseshoe that covers a part of the hoof 201 (Fig. 13) or as covering the whole un- derside of the hoof 201.

The elastomeric sheet 2 is parallel to the underside of the hoof 201. The support members7 of the elastomeric sheet 2 are preferably pointing downwards as shown in Fig. 14. Thehorseshoe 200 may comprise one or more additional layers, such as a top layer 202 and alower layer 203. One or both of top layer 202 and lower layer 203 may be a metal layer. lt should be noted that lop layer 202 and lower layer 203 are optional.

The horseshoe 200 may be attached to the hoof 201 with nails as is known in the art offarriery, or in another suitable manner. The horseshoe 200 may comprise premade holesfor attaching the horseshoe 200 to the hoof 201 with nails, and the holes may be metal reinforced.

EXAl\/l PLE 1 A material with the design of Figs 3-5 was formed from natural rubber with various degrees of ha rd ness. The ha rdness was measured using Shore A methodology. The results are shown in Table 1.Shore A value Standard deviation Sample 1 Sh40 +/- 2-3%Sample 2 Sh50 +/- 2-3%Sample 3 Sh60 +/- 2-3%Sample 4 Sh70 +/- 2-3% Table 1 EXAl\/l PLE 2 A material was formed by using the material from Example 1 covered by 2 mm vinyl mate- ria|.

The impact energy/acceleration was measured using a 3.9 kg dummy head that was allowedto fall 55 cm on a surface covered by the material with 50 Shore or a naked surface without the material. The impact was reduced with 55 % compared to no dampening material.

EXAl\/l PLE 3 A 6.5 kg steel body was allowed to fall onto the 50 Shore A material from 60 cm. The energy was reduced with 30% compared to control.

While the invention has been described with reference to specific exemplary embodiments,the description is in general only intended to illustrate the inventive concept and should notbe taken as limiting the scope of the invention. The invention is generally defined by the claims.

Claims

CLAlMS

1. A head-worn device (100) such as a helmet, a hat or a head band for protecting the headagainst impact shock, the head worn device (100) comprising an elastomeric sheet (2)with a plurality of deformable support members (7) configured to be in contact withthe head or a second layer of the head-worn device, said support members (7) beingconfigured to be deformed upon shock, where the support members (7) has apertures(11) from one side ofthe elastomeric sheet (2)to the other side ofthe elastomeric sheet(2), where the hardness of the elastomeric sheet (2) is from 40 Shore A to 80 Shore A,characterized in that the support members (7) are sepa rated by grooves (8) in the sheet,said grooves (8) having a conical transverse profile and in that the thickness of the elas- tomeric sheet is (2) from 5 to 20 mm.

2. The head worn device (100) according to c|aim 1 which is a head band.

3. The head worn device (100) of c|aim 1 or 2 where there are two parallel sheets (2) of elastomeric material and where the support members (7) are facing towards each other.

4. The head worn device (100) of c|aim 3 where the two parallel sheets (2) are glued to- gether.

5. The head worn device (100) of any one of claims 1 to 4 where the height of the supportmembers (7) in relation to the total thickness of the elastomeric sheet (2) is 25% -75 % of the total thickness of the elastomer layer (2).